Server Error in '/' Application.
Could not load all types from "umbraco.DataLayer, Version=1.0.5948.18143, Culture=neutral, PublicKeyToken=null" due to LoaderExceptions, skipping:
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.Reflection.ReflectionTypeLoadException: Could not load all types from "umbraco.DataLayer, Version=1.0.5948.18143, Culture=neutral, PublicKeyToken=null" due to LoaderExceptions, skipping:
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
Source Error:
An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.
Stack Trace:
[ReflectionTypeLoadException: Could not load all types from "umbraco.DataLayer, Version=1.0.5948.18143, Culture=neutral, PublicKeyToken=null" due to LoaderExceptions, skipping:
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
]
Umbraco.Core.TypeFinder.GetTypesWithFormattedException(Assembly a) +478
Umbraco.Core.TypeFinder.GetClasses(Type assignTypeFrom, IEnumerable`1 assemblies, Boolean onlyConcreteClasses, Func`2 additionalFilter) +336
Umbraco.Core.TypeFinder.GetClasses(Type assignTypeFrom, IEnumerable`1 assemblies, Boolean onlyConcreteClasses, Func`2 additionalFilter) +1008
Umbraco.Core.TypeFinder.FindClassesOfType(IEnumerable`1 assemblies, Boolean onlyConcreteClasses) +62
Umbraco.Core.TypeFinder.FindClassesOfType(IEnumerable`1 assemblies) +45
Umbraco.Core.<>c__DisplayClass3d`1.<ResolveTypes>b__3c() +60
Umbraco.Core.PluginManager.LoadViaScanningAndUpdateCacheFile(TypeList typeList, TypeResolutionKind resolutionKind, Func`1 finder) +46
Umbraco.Core.PluginManager.ResolveTypes(Func`1 finder, TypeResolutionKind resolutionType, Boolean cacheResult) +2583
Umbraco.Core.PluginManager.ResolveTypes(Boolean cacheResult, IEnumerable`1 specificAssemblies) +149
Umbraco.Core.CoreBootManager.InitializeApplicationEventsResolver() +58
Umbraco.Core.CoreBootManager.Initialize() +530
Umbraco.Web.WebBootManager.Initialize() +75
Umbraco.Core.UmbracoApplicationBase.StartApplication(Object sender, EventArgs e) +166
Umbraco.Core.UmbracoApplicationBase.Application_Start(Object sender, EventArgs e) +34
[HttpException (0x80004005): Could not load all types from "umbraco.DataLayer, Version=1.0.5948.18143, Culture=neutral, PublicKeyToken=null" due to LoaderExceptions, skipping:
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
]
System.Web.HttpApplicationFactory.EnsureAppStartCalledForIntegratedMode(HttpContext context, HttpApplication app) +9964625
System.Web.HttpApplication.RegisterEventSubscriptionsWithIIS(IntPtr appContext, HttpContext context, MethodInfo[] handlers) +118
System.Web.HttpApplication.InitSpecial(HttpApplicationState state, MethodInfo[] handlers, IntPtr appContext, HttpContext context) +172
System.Web.HttpApplicationFactory.GetSpecialApplicationInstance(IntPtr appContext, HttpContext context) +339
System.Web.Hosting.PipelineRuntime.InitializeApplication(IntPtr appContext) +296
[HttpException (0x80004005): Could not load all types from "umbraco.DataLayer, Version=1.0.5948.18143, Culture=neutral, PublicKeyToken=null" due to LoaderExceptions, skipping:
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
. System.IO.FileLoadException: Could not load file or assembly 'MySql.Data, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
]
System.Web.HttpRuntime.FirstRequestInit(HttpContext context) +9946132
System.Web.HttpRuntime.EnsureFirstRequestInit(HttpContext context) +90
System.Web.HttpRuntime.ProcessRequestNotificationPrivate(IIS7WorkerRequest wr, HttpContext context) +261
Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.6.1073.0

I found this with UaaS too. "System.Reflection.ReflectionTypeLoadException: Could not load all types from "umbraco.DataLayer, Version=1.0.5948.18143", but it seems that the actual version of the MySql.Data.dll was 6.9.9.0 - an newer version than the expected 6.8.9.0. The following fixed it.

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